A Piece of Mars: Take a look at the windblown stuff in this 0.55×0.625 km (0.34×0.39 mi) scene. Those are intricate patterns of a sort of dune-ripple thing that forms all over on Mars, but not so much on Earth. We call them TARs (transverse aeolian ridges, here are some other examples) because we’re still not sure what they are: dunes or ripples or something else? They’re beautiful, they reflect wind patterns in ways we don’t yet understand, and they might make up a large part of the martian sedimentary rock record. Be glad it’s not your job to try to tease all that out, these things are complex. (HiRISE ESP_051129_1705, NASA/JPL/Univ. of Arizona)

I was at Caltech in California on September 15 2017, with 1500 other people, colleagues, friends and their families, to witness the «end-of-mission» event for Cassini.

Early in the morning, at 2 am, I got up and drove to the site, the mood was of sober festivity, you might have thought we were gathering for a late night summer open air movie. Stands were handing out memorials and snacks. People were tapping others in the back, smiling,watching the big screen with friendly faces pouring out information and feelings.

Later hugs would start, after the signal got smaller and then stopped completely on the screen, hugs would be necessary to hide the tears, half of them tears of happiness that we had accomplished such a wonderful mission, the rest tears of unavoidable chagrin : after a valiant fight against Saturn’s atmosphere, Cassini’s heart stopped, and we lost a star in the sky, someone who communicated with us for more than 20 years since the launch in October 1997.

A Piece of Mars: This 0.95×1 km (.59x.62 mi) scene shows the center of a small dune field. The dunes are shaped by three winds blowing from three different directions: from the west-southwest, east, and south. The north-facing slopes are slip faces made by the south wind, and most of them have bright patches on them that are probably accumulations of airfall dust. Whatever winds brought the dust, none have yet been able to remove it. I’d bet that one of the most recent winds to pick up sand on these dunes blew from the south, because those bright dust patches are still visible on those north-facing slopes, where they’d be protected from southerly winds. (HiRISE ESP_049481_1310, NASA/JPL/Univ. of Arizona).

One of the biggest challenges in popular astronomy is finding specific objects in the night sky. Most nebulae, galaxies, and asteroids are invisible to the naked eye, and locating them in the immense vastness of space has frustrated people for centuries.

Picture taken with a cellphone in the eyepiece of the telescope. The green circle labels the position of Pluto, which is visible.

That’s why most amateur astronomers follow a common but frustrating path. They buy a telescope, look at the moon, a few bright stars, and five planets—and then just give up. After only a few months of use, those telescopes go up for sale on eBay or into the basement.

Last week I traveled from San Francisco to New York City to attend Autumn Starfest, which is sponsored by the Amateur Astronomers Association (AAA) of New York. This star party’s most amazing feature is its location—right in the middle of Manhattan, in the magnificent Central Park! And after flying 2,600 miles (4,100 km), I was eager to show attendees that the Unistellar eVscope will let them see faint targets in the night sky—even the sky of this immense city, with all of its light and other forms of pollution.

And the great news is that the event, and our telescope, were a huge success.

The setup of Starfest in Central Park. It was obviously not a perfect dark sky for astronomy, but a beautiful summer evening for the public (credits: Ed Rojas, AAA.org)

Last week, 5-km asteroid Florence paid Earth a visit—and, using the advanced features of Unistellar’s eVscope, we were able to observe it from a location just outside of San Francisco. This, our first attempt to image an asteroid using the eVscope’s Autonomous Field Detection (ADF) feature, was a huge success, as you can see in the image, which captures what we saw in the telescope’s eyepiece after just three minutes of observing.

Three-min observation of the asteroid (3122) Florence seen in the eyepiece of the eVscope prototype. (Credit: Unistellar)

A Piece of Mars: The sharp line in this 0.625×0.625 km (0.39×0.39 mi) scene is the crest of a long dune in Mars’ southern hemisphere. The sunlit side is also the lee side: the bright streaks are thin sand avalanches (grainflows) that formed when the wind blew too much sand over the crest from the other side. The dark side is completely different. It’s the side facing toward the south pole, and it’s covered in ripples and erosional gullies that are thought to form when winter ice blocks roll down the darker slopes. (HiRISE ESP_024304_1345, NASA/JPL/Univ. of Arizona).

A Piece of Mars: This 2.88×1.13 km (1.79×0.70 mi) scene shows quintessential Mars, with a 670 m diameter impact crater heavily modified by wind erosion. Both the crater floor and the surrounding terrain are covered by what is likely loosely-cemented dust. The texture is that of wind-eroded materials, but to make this texture that material must be fine-grained and uniform in cementation (except where punctuated by craters that are, in turn, also wind-eroded). I’ve never seen a texture like that on Earth. Check out the whole HiRISE image to see how extensive that texture is (and note that I’ve only shown it at half-scale here!) – it’s the dominant feature of this landscape for many hundreds of kilometers. This is in Daedalia Planum, high terrain just southwest of the Tharsis Montes, where equatorial easterly winds might be enhanced by nighttime downslope winds coming down Arsia Mons, the southernmost of the three volcanos (HiRISE ESP_017651_1670, NASA/JPL/Univ. of Arizona)